Ethopropazine, a phenothiazine and antidyskinetic, is used in the treatment of Parkinson’s disease. By improving muscle control and reducing stiffness, this drug permits more normal movements of the body as the disease symptoms are reduced. It is also used to control severe reactions to certain medicines such as reserpine, phenothiazines, chlorprothixene, thiothixene, loxapine, and haloperidol. Unlike other NMDA antagonists, ethopropazine — because of its anticholinergic action — is largely devoid of neurotoxic side effects. Ethopropazine also has a slight antihistaminic and local anesthetic effect.